JPH10278155A - Manufacture of composite material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make a heat controlling layer of composite material usable up to an extremely low temperature by a method wherein the heat controlling layer made of a film, to which a self-adhesive material layer and a reflective layer are respectively coated, is provided to a laminate of prepregs, each of which is formed by infiltrating a thermosetting resin into a carbon cloth and finally the resin is hardened by heating. SOLUTION: Prepregs, each of which is produced by infiltrating a thermosetting resin in a carbon cloth and semi-hardening it, are laminated in combination of predetermined shapes, directions and the number of sheets of the prepreg. In addition, a heat controlling layer 6, which is formed by adhering a self-adhesive material 5 to a thin fluorinated ethylene sheet, on which silver is deposited for forming a reflective layer, is pasted to the prepregs 4. After that, by heating the resultant prepregs under pressure in an autoclave, the prepregs are hardened. At that time, simultaneously the self-adhesive material is also hardened, resulting in strongly bonding the heat controlling layer 6 and a composite material or the composite material 7 with the heat controlling layer 6 is obtained. As the resin used for the prepreg 4, an epoxy resin, a polyester resin or the like is employed. As the self-adhesive material, a silicone-based material is used.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a composite material having a heat control layer, and more particularly to a composite material having a thermal control layer, and more particularly to a solar cell paddle, an aperture antenna, and a satellite housing mounted on space equipment such as artificial satellites. The present invention proposes a composite material having a heat control layer with improved resistance at low temperatures.

[0002]

2. Description of the Related Art FIG. 6 shows an example of a conventional solar cell paddle. In the figure, reference numeral 1 denotes a substrate to which a solar cell is to be attached, which has a structure in which a honeycomb core is sandwiched between skins made of a composite material. I have. Reference numeral 2 denotes a mounting portion of a hinge mechanism for connecting the substrates 1 to each other. The hinge mechanism allows the substrate 1 to be folded, and allows the satellite to be stored in the launch vehicle. Reference numeral 3 denotes a solar battery cell for supplying power to a satellite, and this cell faces the sun in orbit.

[0003] The solar cell paddle for space which is configured in this manner may receive the reflected light of the sun from the earth direction on the surface where the solar cell is not attached on the operation orbit, especially when the altitude of the operation orbit is low. In this case, the temperature of the photovoltaic cell rises and its power generation efficiency decreases. Therefore, in order to prevent a decrease in power generation efficiency, a heat control layer is provided on the surface of the substrate that receives the reflected light of the sun to increase the solar reflectance, thereby preventing the temperature of the solar cell from rising.

FIG. 7 shows a method of forming a heat control layer by a conventional method. First, a prepreg 4 in which a base material such as carbon cloth is impregnated with a thermosetting resin is cured by heating to produce a composite material 7. . After that, the heat control layer 6 having the adhesive 5 was attached to the composite material 7 on the film coated with the reflective layer.

As another method, a white-painted polyvinyl fluoride film is bonded to a composite material with an epoxy resin.

As another method, a white silicon-based paint is applied to a composite material.

[0007] As another method, a fluorinated ethylene film on which silver is deposited is attached to a composite material with an epoxy-based adhesive.

[0008] As another method, a polyimide film on which silver with an adhesive is deposited is attached to a composite material.

[0009]

However, an actual solar cell paddle receives a large temperature change and may be exposed to + 130 ° C. on the high temperature side and −150 ° C. on the low temperature side. The white paint or the bonded thermal control film applied to the surface to which the solar cell is not attached by the conventional technology may be peeled off on the painted surface or the adhesive surface when subjected to a repeated load in such a temperature environment. Was. In particular, the development of a composite material having a heat control layer that is significantly deteriorated on the low temperature side, has improved resistance at low temperatures, and can withstand temperatures as low as -160 ° C. including the allowable range in design has been desired.

In order to avoid peeling of the heat control layer, there is a solution such as fixing the edge of the film by a mechanical method such as screwing when the heat control material is a film. However, the increase in mass is a very serious drawback for satellite-borne equipment that requires weight reduction.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and has as its object to obtain a composite material having a heat control layer which can be used up to a temperature as low as -160.degree.

[0012]

A composite material having a heat control layer according to the first invention is obtained by laminating a prepreg in which a base material such as carbon cloth is impregnated with a thermosetting resin in a predetermined direction, shape and number. Before being heat-cured to the object, a heat control layer composed of a film coated with an adhesive layer and a reflective layer is provided. Thereafter, the resin is heated and cured, and the composite material is cured and, at the same time, the thermal control section layer is attached to the composite material. As a result of trial and error, the inventors have compared the composite material of the present invention with a conventional technology, in which a heat control layer film with an adhesive material is attached to a pre-cured composite material (referred to as “pre-cure”). In the case where the heat control layer is bonded at the same time as the heat curing (referred to as cocure),
It has been found that resistance to exfoliation at significantly lower temperatures is improved. Furthermore, it has been found that the bonding between the composite material and the heat control layer is possible without the use of an adhesive, but the resistance to peeling at low temperatures is reduced when no adhesive is used.

In the method for producing a composite material according to the second aspect of the present invention, a base material such as carbon cloth is first impregnated with a room temperature curable resin. Before curing the resin, a heat control layer composed of a film coated with an adhesive layer and a reflective layer is sequentially provided. Thereafter, the resin is cured to obtain a composite material having a heat control layer.

In the method for producing a composite material according to the third invention, the adhesive layer and the reflective layer are coated before the prepreg impregnated with the thermosetting resin is heat-cured on the substrate such as carbon cloth. A heat control layer composed of a film is provided in order, and the pressure-sensitive adhesive layer and the heat control layer are previously processed into a desired shape. Thereafter, the resin is cured by heating to produce a composite material having a heat control layer having a heat control function only at a desired portion.

In the method for producing a composite material according to the fourth invention, a substrate such as carbon cloth is first impregnated with a room temperature curable resin. Before curing the resin, a heat control layer composed of a film coated with an adhesive layer and a reflective layer is provided in order, and the adhesive layer and the heat control layer are previously processed into a desired shape. Thereafter, the resin is cured by heating to produce a composite material having a heat control layer having a heat control function only at a desired portion.

[0016]

BEST MODE FOR CARRYING OUT THE INVENTION

Embodiment 1 FIG. FIG. 1 is a manufacturing process diagram of a composite material according to Embodiment 1 of the present invention. The steps will be described with reference to FIG. Reference numeral 4 denotes a prepreg, which is obtained by impregnating a thermosetting resin into a base material (called carbon cloth) woven of carbon fibers and semi-curing them, and is laminated in a predetermined shape, direction, and number of sheets. . As shown in FIG. 1 (a), 10 μm
The heat control layer 6 with the silicone-based adhesive 5 having the above thickness is attached to the prepreg 4. FIG. 1B shows a form in which the heat control layer 6 is attached to the prepreg 4. Thereafter, heating and pressurization are performed in an autoclave to cure the prepreg. At this time, the adhesive material is also cured, and the heat control layer 6 and the composite material are firmly bonded. That is, a composite material 7 having a heat control layer 6 is obtained as shown in FIG.

As another example of Embodiment 1, as a prepreg, a unidirectional material in which glass fiber, aramid fiber, quartz fiber, boron fiber, silicon carbide fiber is arranged in one direction on a base material, A cloth material obtained by plain weaving, satin folding, or the like, and a mat material obtained by cutting the above fibers into short nonwoven fabrics can be used. As the resin, a thermosetting resin such as an epoxy resin, a polyester resin, and a cyanate resin can be used. As the pressure-sensitive adhesive, an acrylic pressure-sensitive adhesive, a rubber-based pressure-sensitive adhesive, or the like can be used in addition to the silicone-based pressure-sensitive adhesive.
As the reflective layer, aluminum can be used in addition to silver as a deposit. As an object to be deposited, a film of polyetherimide, polyimide, or the like in addition to ethylene fluoride can be used. As a molding method of the composite material, a curing method using a normal pressure heating furnace by vacuum bagging, a hot pressing method, and the like can be applied in addition to the autoclave method.

Embodiment 2 FIG. FIG. 2 is a manufacturing process diagram of a composite material according to Embodiment 2 of the present invention. As shown in FIG. 2A, a predetermined number, shape, and direction of carbon cloth base materials 8 are laminated, and impregnated with a room temperature curable resin.
The substrate 9 impregnated with the room temperature curable resin is manufactured. After that, 1 layer
A heat control layer 6 with a silicone-based adhesive 5 having a thickness of 0 μm or more is attached. FIG. 2B shows a mode in which the heat control layer 6 is attached to a base material 9 impregnated with a room temperature curable resin. Thereafter, the whole is sealed in a vacuum pack and evacuated, and the pressure-sensitive adhesive 5 is brought into close contact with the substrate 9 impregnated with a room temperature curable resin, and cured at room temperature. Thereafter, post-heat treatment is performed as necessary to obtain a predetermined performance of the carbon fiber reinforced plastic. FIG. 2C shows a composite material 7 having a heat control layer 6.

As another example of Embodiment 2, as a prepreg, a unidirectional material in which glass fiber, aramid fiber, quartz fiber, boron fiber and silicon carbide fiber are arranged in one direction on a substrate, A cloth material obtained by plain weaving, satin folding, or the like, and a mat material obtained by cutting the above fibers into short nonwoven fabrics can be used. A cold-setting resin such as an epoxy resin or a polyester resin can be used as the resin. As the pressure-sensitive adhesive, an acrylic pressure-sensitive adhesive, a rubber-based pressure-sensitive adhesive, or the like can be used in addition to the silicone-based pressure-sensitive adhesive. As the reflective layer, aluminum can be used in addition to silver as a deposit. As an object to be deposited, a film of polyetherimide, polyimide, or the like can be used in addition to ethylene fluoride.

Embodiment 3 FIG. 3 is a manufacturing process diagram according to Embodiment 3 of the present invention. The steps will be described with reference to FIG. As shown in FIG. 3A, a heat control layer 6 having a silicone-based adhesive material 5 having a thickness of 10 μm or more is processed into a desired shape on a silver-deposited thin fluoroethylene sheet as a reflection layer. Thereafter, the heat control layer 6 is attached to the prepreg 4 in which a thermosetting resin is impregnated into a carbon cloth base material. FIG. 3B shows a form in which the heat control layer 6 is attached to the prepreg 4. Thereafter, the mixture is heated and pressurized in an autoclave to be cured. By this manufacturing method, a composite material 7 having a heat control layer 6 is obtained as shown in FIG. Since the heat control layer 6 has been processed in advance, the composite material 7 has a heat control function only at a desired portion.

FIG. 4 is a diagram showing a more detailed manufacturing process of the composite material according to the third embodiment of the present invention. As shown in FIG. 4A, first, a heat control layer 6 having a silicone-based adhesive material 5 having a thickness of 10 μm or more is applied to a silver-deposited thin fluorinated ethylene sheet as a reflective layer by using a double-sided tape 10a. To a plastic film 11. Thereafter, the heat control layer 6 is processed into a desired shape. Thereafter, as shown in FIG. 4B, the plastic film 11 is attached to the acrylic plate 12 using the double-sided tape 10b. Subsequently, FIG.
As shown in (c), it is attached to a prepreg 4 in which a thermosetting resin is impregnated into a base material such as carbon cloth before being cured by heating. Thus, the tape processed into a desired shape can be easily transferred to the prepreg 4. Thereafter, as shown in FIG. 4 (d), after removing the double-sided tape 10a, it is heated and pressed by an autoclave to be cured. In this way, a composite material 7 having a heat control layer 6 as shown in FIG.

Embodiment 4 FIG. 5 is a manufacturing process diagram of a composite material according to Embodiment 4 of the present invention. First, a heat control layer 6 having a silicone-based pressure-sensitive adhesive material 5 having a thickness of 10 μm or more is processed into a desired shape on a thin fluorine-containing ethylene sheet on which silver is deposited as a reflective layer. The base material 8 of the carbon cloth shown in FIG. 5A is impregnated with a room temperature curable resin, and the base material 9 impregnated with the room temperature curable resin is manufactured. Then adhesive 5
Then, the heat control layer 6 is attached to the base material 9 impregnated with the room temperature curable resin. FIG. 5B shows a mode in which the heat control layer 6 is attached to a base material 9 impregnated with a room temperature curable resin. Thereafter, the whole is put in a vacuum bag and evacuated, and the pressure-sensitive adhesive material 5 is brought into close contact with the substrate 9 impregnated with a room-temperature-curable resin, and cured at room temperature. Thereafter, as shown in FIG. 5C, a composite material 7 having a heat control layer 6 is obtained.

[0023]

The effects of the first to fourth inventions are shown in Table 1 in comparison with the prior art. The composite material having the heat control layer of the present invention does not cause any peeling at a temperature of -160 ° C,
It can be used in the temperature range in the space environment. There is no extra increase in mass since no mechanical delamination measures are required.

[0024]

[Table 1]

According to the third and fourth aspects of the present invention, it is possible to process the heat control layer in advance and then attach the heat control layer to the composite material. Obtainable. Since the heat control layer is generally a material such as fluorinated ethylene which is difficult to bond, it is difficult to bond components to the heat control layer. By having no thermal control layer other than the desired part, it is possible to adhere the components on the composite material.

[Brief description of the drawings]

FIG. 1 is a manufacturing process diagram showing Embodiment 1 of a composite material having a heat control layer according to the present invention.

FIG. 2 is a manufacturing process diagram showing Embodiment 2 of a composite material having a heat control layer according to the present invention.

FIG. 3 is a manufacturing process diagram showing Embodiment 3 of a composite material having a heat control layer in a desired portion according to the present invention.

FIG. 4 is a manufacturing process diagram showing Embodiment 3 of a composite material having a heat control layer in a desired portion according to the present invention.

FIG. 5 is a manufacturing process diagram showing Embodiment 4 of a composite material having a heat control layer in a desired portion according to the present invention.

FIG. 6 shows an example of a conventional solar battery paddle.

FIG. 7 is a manufacturing process diagram showing a method for forming a heat control layer by a conventional method.

[Explanation of Signs] 1 Substrate, 2 hinge, 3 solar cells,
4 prepreg, 5 adhesive material, 6 heat control layer, 7 composite material, 8 base material, 9 base material impregnated with room temperature curable resin,
10 double-sided tape, 11 plastic film, 12
Acrylic plate.

Claims (4)

[Claims] 1. A heat control layer having an adhesive layer is provided on a prepreg in which a thermosetting resin is impregnated into a base material such as carbon cloth, and the resin is cured in that state and the heat control layer is bonded. A method for producing a composite material having a characteristic heat control layer. 2. After impregnating a base material such as carbon cloth with a room temperature curable resin, a heat control layer having an adhesive layer is provided,
A method for producing a composite material having a heat control layer, wherein the resin is cured in that state and the heat control layer is bonded. 3. A prepreg in which a thermosetting resin is impregnated into a base material such as carbon cloth, on which a heat control layer having a film-shaped adhesive layer previously processed into a desired shape is provided. A method for producing a composite material having a heat control layer in which a resin is cured and a heat control layer is adhered to only a desired portion and a heat control layer is provided only in a desired portion. 4. After impregnating a base material such as carbon cloth with a room-temperature curable resin, a film-shaped adhesive layer previously processed into a desired shape and a heat control layer are provided in that order on the base material. Curing and bonding the thermal control layer,
A method for producing a composite material having a heat control layer in which only a desired portion has a heat control function.